move gotd fork into repo. (#111)

- update to latest telegram layer
- remove some references to fields in tg.Entities that don't exist in
the schema
- originally added here:
https://github.com/beeper/td/commit/820929062a2ba0104397bc01235ab58a9cff780e
  - referenced here
-
https://github.com/mautrix/telegramgo/commit/124f0967ed195b5a380c9bd02e170ada9710dde3
-
https://github.com/mautrix/telegramgo/commit/4205047aab2e0639217148b5d125bfaab668bd8e

pkg/gotd/proto/container.go

@@ -0,0 +1,96 @@
+package proto
+
+import (
+	"github.com/go-faster/errors"
+
+	"go.mau.fi/mautrix-telegram/pkg/gotd/bin"
+)
+
+// MessageContainerTypeID is TL type id of MessageContainer.
+const MessageContainerTypeID = 0x73f1f8dc
+
+// MessageContainer contains slice of messages.
+type MessageContainer struct {
+	Messages []Message
+}
+
+// Encode implements bin.Decoder.
+func (m *MessageContainer) Encode(b *bin.Buffer) error {
+	b.PutID(MessageContainerTypeID)
+	b.PutInt(len(m.Messages))
+	for _, msg := range m.Messages {
+		if err := msg.Encode(b); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// Decode implements bin.Decoder.
+func (m *MessageContainer) Decode(b *bin.Buffer) error {
+	if err := b.ConsumeID(MessageContainerTypeID); err != nil {
+		return errors.Wrap(err, "consume id of message container")
+	}
+	n, err := b.Int()
+	if err != nil {
+		return err
+	}
+	for i := 0; i < n; i++ {
+		var msg Message
+		if err := msg.Decode(b); err != nil {
+			return err
+		}
+		m.Messages = append(m.Messages, msg)
+	}
+	return nil
+}
+
+// Message is element of MessageContainer.
+type Message struct {
+	ID    int64
+	SeqNo int
+	Bytes int
+	Body  []byte
+}
+
+// Encode implements bin.Encoder.
+func (m *Message) Encode(b *bin.Buffer) error {
+	if m.Bytes < 0 || m.Bytes > 1024*1024 {
+		return errors.Errorf("message length %d is invalid", m.Bytes)
+	}
+	b.PutLong(m.ID)
+	b.PutInt(m.SeqNo)
+	b.PutInt(m.Bytes)
+	b.Put(m.Body)
+	return nil
+}
+
+// Decode implements bin.Decoder.
+func (m *Message) Decode(b *bin.Buffer) error {
+	{
+		v, err := b.Long()
+		if err != nil {
+			return err
+		}
+		m.ID = v
+	}
+	{
+		v, err := b.Int()
+		if err != nil {
+			return err
+		}
+		m.SeqNo = v
+	}
+	{
+		v, err := b.Int()
+		if err != nil {
+			return err
+		}
+		m.Bytes = v
+	}
+	if m.Bytes < 0 || m.Bytes > 1024*1024 {
+		return errors.New("message length is too big")
+	}
+	m.Body = make([]byte, m.Bytes)
+	return b.ConsumeN(m.Body, m.Bytes)
+}